Wouldnt it be much simplier to just build a high back guard on your bucket to keep stuff from rolling out of the bucket and onto your tractor. Looks like armoring up the hood would cause problems with raising the hood for maintenance as it order to make it thick enough to stop a big rock or big log it would have to be fairly heavy which means at some point you have to raise it up by hand.
I would just take some 2" x 1/4" flat bar and weld on a back guard to the FEL bucket similar to dozer blades. You could even put expanded metal in the frame if you wanted to catch really small objects or limbs from coming thru and getting to your radiator. I would make it a bit wider than the hood and about even with the top of the hood with the FEL on the ground. Make a U shaped frame and then a couple of standard in the middle and a cross bar between them should stop about anything large enough to damage the hood and if you wanted, put expanded metal in front of that.